Method and apparatus for applying coating to surgical needles

ABSTRACT

A method and apparatus for applying a lubricant coating to surgical needles utilizes a belt coating system with two endless belts. The endless belts have confronting running sides and are rotated in opposite directions for feeding the surgical needles therebetween. The needles are fed between the confronting running sides and are pressed lightly between the endless belts, whose surfaces have been wetted with the lubricant solution. The needles are cured after coating.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates generally to a system for coating needles, andmore particularly, to a method and apparatus for applying a lubricantcoating to surgical needles used in the medical field.

Surgical needles are used by doctors and other medical professionals toapply sutures, or stitches, by hand through a patient's skin or tissue.Typically, the sutures are used to close wounds or adjoin adjacenttissue, often at the conclusion of a surgical procedure. Coating thesurgical needles with a thin layer of lubricant is done to enhance theperformance of the needle.

2. Description of the Prior Art

It has long been known to apply a lubricant coating to surgical needles.The primary advantage of applying a lubricant, such as a silicone-basedsolution, is that it reduces friction between the needle and the tissue.This reduction of friction lessens the so-called "drag-force" of theneedle passing through the tissue and reduces the pain and discomfortfelt by the patient. A lower drag-force also lessens tissue trauma, orin other words, damage to the tissue caused by the needle passage. Lesstissue trauma results in reduced healing time for the patient. Althoughsurgical needles are generally disposed of after use in a given surgicalprocedure, an effective lubricant solution should stay on the needle forhowever many passes the needle makes through the tissue during itssingle use.

There are several well-known methods of applying a lubricant coating tosurgical needles. Perhaps the most basic method is simply dipping theneedles in a lubricant solution. However, this method is slow andtedious, resulting in poor production output. An updated method ofapplying the lubricant coating is to spray the surgical needles using anatomizer. The atomizer mixes a lubricant solution with large amounts ofair and sprays, or atomizes, the surgical needles. However, sprayingresults in a considerable amount of wasted solution, which increases thecost. Another drawback of spraying is that the mixing of the lubricantsolution with large amounts of air makes combustion of the atomizedsolution a genuine concern. Therefore, the dilutants to be mixed withthe lubricant must be limited to non-combustible materials. Spraying canalso be time consuming because, unless the needles are suspended, theycan only be sprayed one side at a time.

It would be desirable to provide an improved method and apparatus forapplying a lubricant coating to surgical needles that did not have thedrawbacks of conventional methods.

SUMMARY OF THE INVENTION

It is a general object of the invention to provide an improved methodand apparatus for applying a lubricant coating to surgical needles.

It is another object of the invention to provide an efficient andeconomical method and apparatus for applying the lubricant coating tothe surgical needles.

It is still another object of the invention to provide a method andapparatus for positively coating the surgical needles with a lubricantcoating.

It is yet another object of the invention to provide a method andapparatus for applying a lubricant coating to the needle that has a highproduction output.

In accordance with one aspect of the invention, a method for coatingsurgical needles uses a belt coating device with first and secondendless belts disposed to have confronting running sides. The methodcomprises the steps of rotating the first and second endless belts inopposite directions, wetting outer surfaces of the endless belts with alubricant solution, feeding the surgical needles between the confrontingrunning sides of the endless belts, and coating the needles with thelubricant solution as they travel between the coated surfaces of theendless belts.

In accordance with another aspect of the invention, a method for coatingsuture needles comprises the steps of providing an apparatus havingupper and lower endless belts mounted to have confronting running sides,rotating the upper and lower belts in opposite directions to provide apath for transporting the surgical needles between the upper and lowerendless belts, wetting the outer surfaces of the endless belts with alubricant solution for coating the surgical needles, and feeding thesurgical needles between the endless belts so the needles are pressedlightly between the wetted surfaces.

In accordance with another aspect of the invention, a sponge and atrough-like sponge container are positioned above the upper endless beltto contain and transfer the lubricant solution.

In accordance with yet another aspect of the invention, the upper andlower endless belts are offset from one another so the needles can beeasily fed to the lower endless belt.

In accordance with still another aspect of the invention, an apparatusfor coating surgical needles comprises an upper endless belt, a lowerendless belt disposed to have a common running side with the upperendless belt, and means for applying a solution to an outer surface ofthe endless belts. The upper and lower endless belts are rotated inopposite directions and surgical needles are fed between the rotatingbelts to be coated with the solution.

These and other objects, aspects, features and advantages of the presentinvention will become apparent from the following detailed descriptionof the preferred embodiments taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of a belt coating apparatus inaccordance with the present invention;

FIG. 2 is a top plan view of the belt coating apparatus shown in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Generally, the subject invention relates to a method and apparatus forapplying a lubricant solution to surgical needles using a belt coatingsystem. The system uses two endless belts positioned to contact eachother along confronting running sides. A lubricant solution is appliedto wet the outer surfaces of the endless belts. Surgical needles arethen fed along the common running side and pressed lightly between theendless belts to coat the needles with the lubricant solution. Theneedles are collected in a tray as they exit the endless belts and thencured.

One example of a belt coating system 10 used for practicing the subjectmethod of applying a lubricant solution is shown in FIGS. 1 and 2. Theprimary elements of the system 10 include an upper belt assembly 12, alower belt assembly 14, a needle collection tray 16, a drip tray 18 anda sponge 20.

The upper belt assembly 12 is comprised of an endless belt 22 formed asa closed loop and reeved around two rollers 24. Similarly, the lowerbelt assembly 14 has an endless belt 26 forming a closed loop and reevedaround two rollers 28. The dimensions of the belts can vary and willdepend on the desired size and output capability of the device. However,typical dimensions will find the endless belts to be approximately 14inches to 16 inches in length (roller to roller) and 4 inches in width.The rollers 24 and 28 can be, for example, 1 inch in diameter andpreferably have a length comparable to the width of the belts. Theendless belts are readily available commercial-grade belts and should benon-absorbable, preferably with a textured outer surface for retaining,or holding, small amounts of the lubricant solution.

As best seen in FIG. 1, the upper and lower belts should be positionedto have confronting running sides, or surfaces, 29a and 29b. Morespecifically, the upper belt assembly 12 is supported just above thelower belt assembly 14 such that a bottom surface 29a of the upperendless belt 22 contacts a top surface 29b of the lower endless belt 26.As will be appreciated, the upper and lower endless belts are rotated inopposite directions such that the confronting running surfaces 29a and29b are travelling in the same direction. In the embodiment shown inFIG. 1, the rollers 24 of the upper belt assembly are rotatedcounter-clockwise about their longitudinal axis, and the rollers 28 ofthe lower belt assembly are rotated clockwise about their longitudinalaxis. As is conventional, typically only one of the rollers in each beltassembly serves as a driving roller and is rotated by unshown drivingmeans, and the other roller is driven, or rotated, by the endless belt.

As evident in both FIGS. 1 and 2, the belt assemblies are laterallyoffset, with the lower belt assembly 14 being disposed slightlyforwardly from the upper belt assembly 12 (with respect to the traveldirection of the running surface, that is, with the inlet end considered"forward" and the outlet end considered "rearward"). This offsetarrangement makes it easier to feed the surgical needles between thebelt assemblies as discussed in more detail below. Extending the upperbelt assembly past the rearward end of the lower belt assembly also aidsin dispensing the coated surgical needles into the collection tray. Theporous sponge 20 is provided in a trough-like sponge container 30supported above the upper belt assembly 12 and serves as a transfermedium for transferring the lubricant solution to the upper endless belt22. As best seen in FIG. 2, the sponge 20 and container 30 arepreferably V-shaped to allow for a greater surface area of the sponge tocontact the upper endless belt and produce a thorough application of thelubricant solution. Of course, other means for wetting the endless beltswith the lubricant solution are within the scope of the invention.

With reference to FIG. 1, a forward end scraper or doctor blade 31 ofthe container extends downwardly and contacts the upper endless belt 22to prevent excess lubricating solution from being applied.

The drip tray 18 is disposed beneath the lower belt assembly 14 tocollect excess lubricant solution that runs off the belt coating system.As shown in the figures, the drip tray is preferably slightly wider thanthe endless belts and extends past the forward end of the lower beltassembly 14. Fins 32 are provided below the lower surface of the lowerendless belt 26 to continually clean, by gently scraping, the lowerendless belt. The fins are preferably supported by an unshownspring-loaded mechanism on a frame of the system and biased against thelower endless belt. Fins 34 can also be biased against the rearward endsof the upper and lower endless belts. These fins also continually cleanthe endless belts, but in addition help to remove any surgical needlesadhered to the upper or lower endless belts and guide the needles intothe collection tray 16. Fins 34 are also supported by an unshownspring-loaded mechanism on the frame of the belt coating system. Othercomparable means for cleaning and/or removing the coated needles fromthe endless belts can be provided without departing from the scope ofthe present invention.

The collection tray 16 is positioned at the rearward, or exit, end ofthe belt coating device 10 for receiving the coated surgical needles asthey exit from between the endless belts. As shown in FIG. 2, thecollection tray is also wider than the endless belts.

An example of using the belt coating system for applying a lubricantsolution to the surgical needles in accordance with the subjectinvention will be discussed below.

In preparation for coating the surgical needles, a lubricant solution isdispensed into the trough-like container 30 to soak the porous sponge20. Many well-known lubricant solutions can be used in practicing themethod of the subject invention. For example, an aqueous siliconecoating solution with a silicone concentration of 16% non-volatilecontent provides excellent results.

The upper and lower endless belts 22 and 26 are driven in oppositedirections by appropriate drive means (unshown), as discussed above, atapproximately 45 inches per minute. With the sponge 20 in direct contactwith the upper endless belt as shown in FIG. 1, the lubricant solutionis transferred to the upper belt surface as it travels in aright-to-left direction across the sponge. The forward end scraper 31 ofthe container prevents excess amounts of lubricant solution from beingapplied. As the upper and lower endless belts contact each other alongthe confronting running sides 29a and 29b, lubricant solution istransferred to the outer surface of the lower endless belt 24 from theupper endless belt 22. To coat the surgical needles in accordance withthe subject invention, one or more needles are placed on the uppersurface at the forward end of the lower endless belt 26. Since the lowerendless belt is offset from the upper endless belt 22, the needles canbe easily placed on the lower endless belt without interference from theupper endless belt. Once the needles are placed on the lower endlessbelt, they are fed in the left-to-right direction, with respect to FIG.1, between the confronting running sides 29a and 29b between the upperand lower endless belts.

The needles are then pressed lightly between the upper and lower endlessbelts. Since both endless belts are coated with the lubricant solution,the solution contacts both sides of the needles and the needles arecompletely coated. As the needles exit the confronting running sides atthe rearward ends of the upper and lower endless belts, they are fedinto the curing tray 16. Fins 34 assist in removing the coated needlesfrom the belts if necessary. Fins 32 below the lower endless belt 26continuously scrape off excess lubricant solution and allow the solutionto fall into the drip tray.

The automatic operation of the belt coating system allows surgicalneedles to be continuously fed through lubricant-coated upper and lowerendless belts. This results in a very high output of completely coatedsurgical needles. It will also be appreciated that besides coatingsurgical needles, staples or other similar items can be coated in thesame manner to achieve the same benefits. There is also a very efficientuse of lubricant solution since the amount applied to the upper andlower endless belts can be regulated by the amount of solution dispensedto the porous sponge 20 and the position of the forward end scraper 31on the container. The excess solution collected in the drip tray canalso be recycled and used again if desired.

After the coated needles are deposited in the curing tray, they arecured, for example, at 150° C. for two hours.

Although specific embodiments of the present invention have beendescribed above in detail, it will be understood that this descriptionis merely for purposes of illustration. Various modifications of andequivalent structures corresponding to the disclosed aspects of thepreferred embodiments in addition to those described above may be madeby those skilled in the art without departing from the spirit of thepresent invention which is defined in the following claims, the scope ofwhich is to be accorded the broadest interpretation so as to encompasssuch modifications and equivalent structures.

What is claimed is:
 1. A method for coating surgical needles using abelt coating device with first and second endless belts each having aforward and and a rearward end and disposed to have confronting runningsides, said method comprising the steps of:rotating the first and secondendless belts in opposite directions; wetting outer surfaces of theendless belts with a lubricant solution; feeding the surgical needlesbetween the confronting running sides between the endless belts; andcoating the needles with the lubricant solution as they travel from theforward ends to the rearward ends between the wetted surfaces of thefirst and second endless belts.
 2. A method according to claim 1,further comprising the step of wetting the outer surface of the firstendless belt with a sponge disposed to be in contact with the firstendless belt and containing the lubricant solution.
 3. A methodaccording to claim 2, further comprising the step of regulating theamount of lubricant solution applied by the sponge to the first endlessbelt.
 4. A method according to claim 1, further comprising the step ofcatching the coated surgical needles with a tray as they exit frombetween the first and second endless belts.
 5. A method according toclaim 1, further comprising the step of cleaning the second endless beltby continuously removing excess lubricant solution therefrom.
 6. Amethod according to claim 5, further comprising the step of collectingthe excess lubricant coating removed in the cleaning step.
 7. A methodaccording to claim 1, further comprising the step of scraping therearward ends of the first and second endless belts to remove any coatedsurgical needles adhered thereto.
 8. A method for coating surgicalneedles comprising the steps of:providing an apparatus having upper andlower endless belts mounted to have confronting running sides with anentry end and an exit end; rotating the upper and lower endless belts inopposite directions for transporting surgical needles disposedtherebetween along the confronting running sides and in a transportdirection; wetting the outer surfaces of the upper and lower endlessbelts with a lubricant solution for coating the surgical needles; andfeeding the surgical needles along the confronting running sides betweenthe upper and lower belts such that the needles are pressed between thewetted surfaces and coated with a layer of lubricant solution.
 9. Amethod according to claim 8, further comprising the steps of:providing asponge positioned above and in contact with the upper endless belt;applying the lubricant solution to the sponge; and running the upperendless belt across the sponge to transfer the lubricant solutionthereto.
 10. A method for coating surgical needles comprising the stepsof:providing an apparatus having upper and lower endless belts mountedto have confronting running sides with an entry end and an exit end;rotating the upper and lower endless belts in opposite directions fortransporting surgical needles disposed therebetween along theconfronting running sides and in a transport direction; wetting theouter surfaces of the upper and lower endless belts with a lubricantsolution for coating the surgical needles; feeding the surgical needlesalong the confronting running sides between the upper and lower beltssuch that the needles are pressed between the wetted surfacer and coatedwith a layer of lubricant solution; providing a sponge positioned aboveand in contact with the upper endless belt; applying the lubricantsolution to the sponge; running the upper endless belt across the spongeto transfer the lubricant solution thereto; providing a container forholding the sponge; and preventing excess solution from being applied tothe upper endless belt by providing a scraper on a forward end of thecontainer with respect to the transport direction.
 11. A methodaccording to claim 10, further comprising the step of shaping the spongeand the container to have a linear length that is greater than a widthof the upper endless belt.
 12. A method according to claim 8, furthercomprising the steps of:providing a curing tray at the exit end of theconfronting running sides; and catching the coated surgical needlesexiting from between the upper and lower endless belts.
 13. A methodaccording claim 8, further comprising the steps of:providing fins biasedagainst a lower surface of the lower endless belt; and continuouslycleaning the lower endless belt with the fins to remove excess solution.14. A method according to claim 13, further comprising the stepsof:providing a drip tray beneath the lower endless belt; and collectingthe excess solution removed by the fins.
 15. A method according to claim8, further comprising the steps of:providing fins at rearward ends ofthe upper and lower belts; and scraping the rearward ends of the upperand lower belts to remove any coated needles adhered to the endlessbelts.
 16. A method according to claim 8, further comprising the stepsof laterally offsetting the upper and lower endless belts to positionthe lower endless belt forward of the upper endless belt.
 17. A methodaccording to claim 11, wherein the sponge and the container aresubstantially V-shaped, with an angled portion of the V-shaped containerdisposed closest to the exit end for increasing the surface area of thesponge contacting the upper endless belt.